Claims
- 1. An acoustic transmission system for acoustically coupling to an associated transducer and providing a relatively smooth output response therefrom, said system comprising in combination, first duct means having one end acoustically coupling to the transducer and its other end open, said first duct means effecting a first acoustical impedance, second duct means having one end acoustically connected to said first duct means, the other end of said second duct means which is remote from the first duct means being acoustically blocked, acoustic damping means in said second duct means, and said acoustic damping means having the characteristic impedance of said second duct means.
- 2. An acoustic transmission system as in claim 1 wherein the second duct means is of the same length as said first duct means and wherein an acoustically closed end terminates the remote end of said second duct means.
- 3. An acoustic transmission system as in claim 1 wherein said first duct and said second duct are of substantially the same length and cross section.
- 4. A system as in claim 1 further including a common duct means for acoustically coupling the transducer to said first and second duct means, the open end of said first duct means enabling the system to be acoustically coupled to an ear cavity and the blocked end of said second duct means providing a high impedance termination, and a second damping means having a similar impedance to said first damping means mounted in said first duct means, whereby the impedance presented by said system to sound from said transducer is relatively constant throughout the operating frequency range.
- 5. A system as in claim 4 wherein said common duct means couples at a junction with said first and second duct means, and wherein said first damping means is positioned in said second duct means adjacent the junction of said second duct means and said common duct means, and said second damping means is positioned in said first duct means adjacent the junction of said first duct means and said common duct means whereby a relatively smooth output response is obtained from said transmission system.
- 6. A system as in claim 1 wherein second acoustic damping means are positioned in said first duct means, said second damping means having a similar impedance as said acoustic damping means in said second duct means and having the characteristic impedance of said first duct means, and said first duct means and said second damping means providing an acoustical impedance which is complementary to the acoustical impedance of the second duct means and the acoustic damping means positioned therein whereby a relatively smooth output response is obtained from said transmission system.
Parent Case Info
This is a continuation of application Ser. No. 444,036, filed Feb. 20, 1974 now abandoned.
US Referenced Citations (5)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1,158,116 |
Nov 1963 |
DT |
Continuations (1)
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Number |
Date |
Country |
Parent |
444036 |
Feb 1974 |
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